Device for constructing long culverts or continuous concrete tubes



T.NOSE

Feb. 24, 1931.

DEVICE FOR GONSTRUCTING LONG CULVERTS OR CONTINUOUS CONCRETE TUBES Filed Oct. 26, 1928 INVENTOR' M K .V

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ATTORNEY$ Patented Feb. 24, 1931 UNITED STATES PATENT OFFICE DEVICE FOR CONSTRUCTING LONG CULVERTS OR CONTINUOUS CONCRETE TUBES Application filed October 26, 1928.

This invention relates to an improvement in a device for constructing long culverts or continuous concrete tubes for sewers and cable ducts and the like.

The method of constructing culverts by using a core for moulding concrete culverts consisting of an outer tube made'of elasticsubstance smaller in diameter than the bore to be formed, and an inner tube of flexible but sub- ;3 stantially non-expansible material, stuffed in said outer tube and larger in diameter than said outer tube is known in Noses U. S. Patent No. 1,57 0,915. That method, however, is accompanied by many disadvantages in con- 15 structing a long culvert. For example, the lack of support for a moulding core causes it to float up on account of the upward pressure due to the weight of liquid concrete and consequently a straight bore cannot be obtained.

29 That method has no means for facilitating the manufacture of long tubes. Therefore, it involves considerable time and expense. Besides, the cores used have such drawbacks that they are heavy and apt to be damaged.

Moreover, they are too weak to resist pressure.

A primary object of this invention is to provide means for supporting the core in its position so as to prevent the cores from be- 3o'coming uneven on account of the upward pressure due to the weight of liquid concrete.

Another object is to provide means for laying a long culvert, which consists of several sections made at the same time, each con- 35 nected with the adjacent one by using the bag-like cores connected in series. Thus, the time and cost for manufacturing long culverts are considerably economized. Another object is to obtain novel cores suitable for manu- 40 facturing long light culverts of concrete or the like such as resist the pressure of fluid.

In the accompanying drawings,

Fig. 1 is a longitudinal sectlona-l view of a general arrangement for manufacturing a 45 long culvert,

Fig. 2, a cross sectional view of a part of the long culvert manufactured according to this invention,

Fig. 8, is a longitudinal sectional view showing the method of connecting the parts Serial No. 315,297.

moulded separately by a core according to this invention,

Fig. 4, a front sectional View showing the process of manufacturing a cable duct.

Fig. 5, a cross sectional View of the same.

In Figs. 1 to 3, 1 is a concrete stand laid longitudinally along the bottom of a concrete duct having its upper surface 2 curved to'coincide with the curvature of the bore. 3 and 4 are longitudinal and circular bars of ironreinforcement respectively. 5 is a core made of an inner and an outer flexible tube a and b respectively, and an intermediate member 0 of canvas or fabric interwoven with metallic wire. Core 5 is of closed-bag shape with a small inlet opening atone side and two connecting means 7 at both ends.

In the moulding operation, the concrete stand 1 is first'laid out to the full length to be moulded. placed in series, and the iron reinforcement placed in its position. The concrete is then poured between the plate 8 and the inflated cores. Thus, many sections of a continuous culvert may be moulded at the same time, leaving a short space designated 9 between the adjacent sections.

According to this invention, after drawing out the moulding cores (not shown in the drawings), short bag-shaped cores are introduced into the bore in the space to be connected. Air supply pipes 10 are inserted through the inlet mouth 11, and air or other fluid is supplied to the bag to inflate it to its full diameter. Then, concrete is supplied to the space to form a connection for two adjacent sections. After the air supply pipe is removed, the core is exhausted and can be drawn out easily from one end of the culverts. out the supply pipe 10 may be closed without any trouble. Thus, long culverts are made with least possible time and expense.

Figs. 4 and 5 show the process of moulding cable ducts according to this invention. The cable ducts include many long holes 14 arranged vertically and horizontally. In this case, the ducts are divided into many sections which are moulded in a similar way as explained before, but the air-supply pipes m Then, the moulding cores are The small openings left by drawing such as shown in Figs. 1 to 3 cannot be used because it is impossible to draw them out. Thus, the cores used to form a connection for the sections of a duct are connected by a flexible air pipe 12 end to end and may be connected by strings or ropes 15. After the sections are moulded leaving open spaces be tween them, the above-mentioned cores are inserted in their positions and'supplied with suitable fluid from one end of supply pipes to inflate the core'to its full diameter and the concrete is supplied to mould connections around the cores. The fluid in the cores is discharged and the cores are drawn out from one end of the duct. Thus, the continuous cable duct is completed.

The core consists of an outer tube Z),'an an inner tube (1 and an intermediate layer 0. The outer tube 5 is formed of elastic and eX pansible material such as india rubber and metallic gauze wire or otherwise.

The core may also be formed of canvas or fabric interwoven wlth metalllc wire or otherwise, theinner and outer surfaces being both lined with thin layers of india rubber.

Claims:

1:. The method of forming continuous tubes which consists in laying a continuous base, moulding. on said base a plurality of short tube-forming sections in separated end-toend relation, inserting inflatable cores in the spaces between adjacent sections with the ends of said cores extending into the opposling ends of the sections, inflating said cores, filling the spaces around the inflated cores with tube-forn'iing material, deflating said cores and withdrawing them through one end of the tube. V

2. The method of forming continuous tubes whichconsists in laying a continuous base, moulding on said base a plurality of short tube-forming sections in separated end-toend relation, inserting inflatable cores in the spaces between adjacent sections with the ends of said cores extending into the opposing ends of the sections, connecting said cores in series for inflation from a single source of fluid supply, inflating said cores, filling the spaces around the inflated cores with tubeforming material, deflating said cores and withdrawing them through one end of the tube.

0. ,A core for forming continuous tubes, comprising a plurality of short inflatable flation from a single source of fluid supply,

and means for withdrawing said members as a unit from one end of a complete tube.

TOICHI. NOSE. 

